The general objective of this research grant is to develop a radioisotope data processing and display system within the Massachusetts General Hospital and to investigate its interactive and simultaneous use in processing data from a variety of nuclear medicine sources. Towards this end the specific objectives are to: 1. Further develop NUMEDICS, our radioisotope data processing facility developed around a PDP-9 computer, to provide increased capability for simultaneous collection, processing and display of nuclear medicine data. 2. Explore theoretically and experimentally the utility of techniques for image processing and display. 3. Develop new techniques for processing and display of dynamic function data and determine their utility. 4. Study the application of this facility and these techniques in clinical nuclear medicine.